I Have Something, Need Quick Help

I was recently a retard and downloaded a clearly visible virus in hopes of getting something for free. My GUI started messing up and and the arrows in the bottom right of the task bar started duplicating and the other icons wouldn't show. I looked around online and downloaded SDFix and ran that in safe mode, this seemed to fix the problem I was having but now I have even more problems that aren't being fixed. Every time I run adaware it detects like 15 bad files and AVG hasen't told me anything new yet.
But as for the current problem I am having, my computer seems to be running really slow at times and it feels like it 'skips beats'. Also when I try to access the internet I keep hearing a bunch of clicking sounds when I'm not clicking anything. I also keep getting random pop-ups about spy-ware removal and free scans, and "your computer needs scanning, click here". I know these are bad so I haven't clicked any of them, but I've never had this problem before. Also when I start my computer I get a rundll32.exe error saying the memory could not be "read' and then one saying it cannot "written". This is very frustrating and nothing seems to help. Please help me in any way because I really don't want to reinstall windows.

Thanks for the reply but I actually just went ahead and reinstalled windows. I found the disks and it seemed better. But now I have a different problem,
after I installed windows on my computer again I tried to go online to install some updates. I realized I could not get online. I usually used a wireless card but then I realized that I need to reinstall the drivers for it but because of the lateness of the hour my parents were in bed at their house and couldn't not find it for me. I tried plugging the router directly into the computer but for some reason that still didn't work. I have no idea what to do right now and any help at all would be much appreciated. Thank you.